weed mount ls paginate the results

fix https://github.com/chrislusf/seaweedfs/issues/787

weed/filesys/dir.go

@@ -239,9 +239,17 @@ func (dir *Dir) ReadDirAll(ctx context.Context) (ret []fuse.Dirent, err error) {
 
 	err = dir.wfs.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
 
+		paginationLimit := 1024
+		remaining := dir.wfs.option.DirListingLimit
+
+		lastEntryName := ""
+
+		for remaining >= 0 {
+
 			request := &filer_pb.ListEntriesRequest{
 				Directory:         dir.Path,
-			Limit:     uint32(dir.wfs.option.DirListingLimit),
+				StartFromFileName: lastEntryName,
+				Limit:             uint32(paginationLimit),
 			}
 
 			glog.V(4).Infof("read directory: %v", request)
@@ -262,6 +270,15 @@ func (dir *Dir) ReadDirAll(ctx context.Context) (ret []fuse.Dirent, err error) {
 					ret = append(ret, dirent)
 				}
 				dir.wfs.listDirectoryEntriesCache.Set(path.Join(dir.Path, entry.Name), entry, cacheTtl)
+				lastEntryName = entry.Name
+			}
+
+			remaining -= len(resp.Entries)
+
+			if len(resp.Entries) < paginationLimit {
+				break
+			}
+
 		}
 
 		return nil
@@ -351,10 +368,7 @@ func estimatedCacheTtl(numEntries int) time.Duration {
 		// 10 ms per entry
 		return 100 * time.Second
 	}
-	if numEntries < 100000 {
-		// 10 ms per entry
-		return 1000 * time.Second
-	}
+
 	// 2 ms per entry
 	return time.Duration(numEntries*2) * time.Millisecond
 }